HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: M600455-MCP200v1 6/9/1551    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Glossary Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Brikos, C. Articles by Saklatvala, J. Search for Related Content PubMed PubMed Citation Articles by Brikos, C. Articles by Saklatvala, J. Social Bookmarking                      What's this?

Molecular & Cellular Proteomics 6:1551-1559, 2007.
© 2007 by The American Society for Biochemistry and Molecular Biology, Inc.

---

Research

Mass Spectrometric Analysis of the Endogenous Type I Interleukin-1 (IL-1) Receptor Signaling Complex Formed after IL-1 Binding Identifies IL-1RAcP, MyD88, and IRAK-4 as the Stable Components^*

Constantinos Brikos^,,¶, Robin Wait, Shajna Begum, Luke A. J. O'Neill^,|| and Jeremy Saklatvala^,||

From the Kennedy Institute of Rheumatology Division, Faculty of Medicine, Imperial College London, London W6 8LH, United Kingdom and the School of Biochemistry and Immunology, Trinity College Dublin, Dublin D2, Ireland

We investigated the composition of the endogenous ligand-bound type I interleukin-1 (IL-1) receptor (IL-1RI) signaling complex using immunoprecipitation and tandem mass spectrometry. Three proteins with approximate molecular masses of 60 (p60), 36 (p36), and 90 kDa (p90) became phosphorylated after treatment with IL-1. Phosphorylation in vitro of p60 has been reported previously, but its identity was unknown. We showed using tandem mass spectrometry that p60 is identical to interleukin-1 receptor-associated kinase (IRAK)-4. MS also enabled detection of IL-1, IL-1RI, IL-1 receptor accessory protein (IL-1RAcP), and myeloid differentiation primary response protein 88 (MyD88) in the complex. The p60 protein (IRAK-4) was the earliest component of the complex to be phosphorylated. Phosphorylated IRAK-4 from the receptor complex migrated more slowly in SDS-PAGE than its unphosphorylated form as did recombinant IRAK-4 autophosphorylated in vitro. Phosphorylation was restricted to serine and threonine residues. IRAK-4, p36, IL-1RAcP, and MyD88 bound to the liganded receptor within 15 s of activation by IL-1 and remained associated upon prolonged activation, suggesting that the signaling complex is very stable. The p90 phosphoprotein was only transiently associated with the receptor. This behavior and its size were consistent with it being IRAK-1. Our work revealed that liganding of IL-1RI causes its strong and stable association with IL-1RAcP, MyD88, and the previously unidentified protein p60 (IRAK-4). The only component of the IL-1RI signaling complex that dissociated is IRAK-1. Our study is therefore the first detailed description of the endogenous IL-1RI complex.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				C. M. Cahill and J. T. Rogers Interleukin (IL) 1{beta} Induction of IL-6 Is Mediated by a Novel Phosphatidylinositol 3-Kinase-dependent AKT/I{kappa}B Kinase {alpha} Pathway Targeting Activator Protein-1 J. Biol. Chem., September 19, 2008; 283(38): 25900 - 25912. [Abstract] [Full Text] [PDF]

				D. Neumann, C. Kollewe, A. Pich, P. Cao, K. Resch, and M. U. Martin Threonine 66 in the death domain of IRAK-1 is critical for interaction with signaling molecules but is not a target site for autophosphorylation J. Leukoc. Biol., September 1, 2008; 84(3): 807 - 813. [Abstract] [Full Text] [PDF]

				C. Jeulin, V. Seltzer, D. Bailbe, K. Andreau, and F. Marano EGF mediates calcium-activated chloride channel activation in the human bronchial epithelial cell line 16HBE14o-: involvement of tyrosine kinase p60c-src Am J Physiol Lung Cell Mol Physiol, September 1, 2008; 295(3): L489 - L496. [Abstract] [Full Text] [PDF]